package com.itheima.contorller;


//文件的上传和下载处理

import com.itheima.common.R;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/common")
public class CommonController {
    @Value("${reggie.path}")
  private String basePath;
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file){

        //原始文件名
        String originalFilename = file.getOriginalFilename();
        String substring = originalFilename.substring(originalFilename.lastIndexOf("."));
        //随机文件名
        String s = UUID.randomUUID().toString() + substring;

        try {
            file.transferTo(new File(basePath+s));
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

        return R.success(s);
    }
     @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        try {
            //通过输入流读取文件
            FileInputStream fileInputStream = new FileInputStream(new File(basePath+name));

            //通过输出流将文件写回浏览器
            ServletOutputStream outputStream = response.getOutputStream();

            int len=0;
            byte[] bytes =new byte[1024];
            while ((len=fileInputStream.read(bytes))!=-1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }
            outputStream.close();
            fileInputStream.close();


        } catch (Exception e) {
            throw new RuntimeException(e);
        }
    }
}
